Introduction of Chemical Bonding

Introduction of Chemical Bonding

Chemical bonding can only be put into perspective and be illustrated into a small number of real life example bonding. But the best are the Human Bonding. This is because Human are diverse and vary, however they still need each other. By, definition human bonding can be describe as “ the process of development of a close, interpersonal relationship. It most commonly takes place between family members or friends, but can also develop among groups, such as sporting teams and whenever people spend time together.” Which is very similar to the behaviour of atom, where atoms form chemical bonds in order to make their most outer electron shells (valence shell) more stable.

Chemical bonding between atom happen because they need to “follow” and “obey” the octet rule. Atoms follow the octet rule because they always seek the most stable electron configuration. The octet rule states that elements gain or lose electrons to attain an electron configuration of the nearest noble gas. Noble gases have complete outer electron shells, which make them very stable. Other elements also seek stability, which cause their tendency to have bonding behavior to become an noble gas.

A Brief Past on Chemical Bonding Concepts

• In 1852, E. Frankland proposed the concept of valence. He suggested that each element formed compounds with definite amounts of other elements due to a valence connection.

• Five years later, F.A. Kekule and others proposed a valence of 4 for carbon. Lines were used to represent valence, and this helped the development of organic chemistry

• Following the discoveries of electrons by J.J. Thompson, Gilbert Newton Lewis proposed to use dots to represent valence electrons. His dots made the valence electrons visible to chemists. Example of Lewis dot diagram of NH3:

• With the discovery of X-ray, the X-ray diffractions by crystal allow chemist to calculate details of bond length and bond angles. These data prompted Linus Pauling to look at The Nature of Chemical Bond, a book that introduced many new concepts such as the resonance (resonance structures are two forms of a molecule where the chemical connectivity is the same but the electrons are distributed differently around the structure), electronegativity (Electronegativity is a measure of the tendency of an atom to attract a bonding pair of electrons), ionic bond (Ionic bonding is a type of chemical bond that involves the electrostatic attraction between oppositely charged ions, and is the primary interaction occurring in ionic compounds. ), and covalent bond ( a chemical bond that involves the sharing of electron pairs between atoms).

• Nevil Vincent Sidgwick and H.E. Powell paid their attention to the lone pairs in a molecule. They developed the valence bond theory, the VSEPR (Valence Shell Electron Pair Repulsion) theory. VSEPR is a valence shell electron pair repulsion, this theory was based on the idea that pairs of electron around the central of atom with the same charge want to be as far as possible from each other. That is why they push away each other and try to be as far as possible.